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The structural design of molecular machines and motors endows them with externally controlled directional motion at the molecular scale. Molecular machines based on both interlocked and non-interlocked molecules and driven by a variety of external stimuli such as light, electrical-or thermal energy, and chemical-or redox processes have been reported. With the field moving forward, they were incorporated into surfaces and interfaces to realize amplified directional molecular motion at the nanoscale which can be applied in the control of macroscopic material properties. More recently, molecular motors and molecular machines based on interlocked molecules have been organized into three dimensional materials to expand their functionality in the solid state and enrich their applicability.

This rapid rise in temperatures is linked to a growing energy imbalance in the Earth’s system, intensified by human-induced greenhouse gas emissions.

Ocean Warming Accelerates at an Alarming Rate

The rate at which the oceans are warming has more than quadrupled in the past 40 years, according to a new study.

Can you make something invisible? Neil deGrasse Tyson and comedian Negin Farsad discover the science behind invisibility with professor of physics and optical science, Greg Gbur. What would real-life invisibility look like?

Can you be invisible in other parts of the magnetic spectrum? We discuss transparency versus invisibility and how metamaterials help us interact with different wavelengths. What does light have to do in order to make something invisible? We break down invisibility cloaks and other invisibility devices from fiction.

Could you make yourself invisible to all parts of the electromagnetic spectrum? We explore the main challenges in achieving invisibility and the difference between passive and active invisibility. How useful of a power would it be?

We discuss the interaction between waves and matter. What makes some waves reflect off matter and others pass through? Learn about x rays and how they work, plus, an at-home invisibility trick using prisms. Finally, could you make someone invisible to time?

As their primary food source becomes less accessible, the bears enter longer fasting periods, leading to declining health and population numbers.

“A loss of sea ice means bears spend less time hunting seals and more time fasting on land,” said Louise Archer, a postdoctoral researcher and lead author of the study.

This prolonged fasting drains polar bears’ energy reserves, reducing their ability to reproduce and raise cubs. Without enough stored fat, female bears struggle to give birth and nurse their young. Over time, this energy deficit has led to a sharp population decline.

Using the Gran Telescopio Canarias (GTC) and the Apache Point Observatory (APO), an international team of astronomers has detected 19 pulsation modes in an ultra-massive white dwarf known as WD J0135+5722. The discovery, presented on the arXiv preprint server, makes WD J0135+5722 the richest pulsating ultra-massive white dwarf known to date.

White dwarfs (WDs) are stellar cores left behind after a star has exhausted its nuclear fuel. Due to their high gravity, they are known to have atmospheres of either pure hydrogen or pure helium. However, a small fraction of WDs shows traces of heavier elements.

In pulsating WDs, luminosity varies due to non-radial gravity wave pulsations within these objects. One subtype of pulsating WDs is known as DAVs, or ZZ Ceti stars—these are WDs of spectral type DA, having only hydrogen absorption lines in their spectra.

ANEMEL researchers have created a catalyst for water splitting that’s efficient and stable, without relying on scarce platinum group metals (PGMs). The study, recently published in Energy & Environmental Science, reports a high-performance PGM-free catalyst for the cathode in water electrolysis, responsible for the reaction that creates green hydrogen.

Current anion exchange membrane (AEM) water electrolyzers rely on PGMs, which are scarce and expensive. Specifically, these metals are used as catalysts at the cathode, where hydrogen is generated. However, ANEMEL AEM electrolyzers avoid PGMs, opting instead for more abundant metals such as nickel. This is essential to enable the wide adoption of electrolyzers: it helps to decrease the cost of electrolyzer components and improve their recyclability, reducing waste and providing a competitive advantage.

This requires investigating innovative ways to ensure electrolyzers perform at least as well, if not better than, those made with PGMs. After all, platinum and other metals in this group offer excellent activity and stability, especially at high current densities in electrolyzer environments, something PGM-free catalysts still don’t.

Simultaneous measurements of the optical force and power exerted by a collimated laser beam on a 50-nm-thick silicon nitride lightsail membrane suspended by compliant micromechanical springs quantify the radiation pressure, enabling further multiphysics studies of radiation pressure forces on macroscopic objects.

Electromagnetic absorbers are essential in energy, stealth, and communication technologies, yet current designs underperform. A research team has introduced ultra-thin absorbers nearing theoretical efficiency limits, promising transformative industrial applications.

Absorbing layers are essential to advancements in technologies like energy harvesting, stealth systems, and communication networks. These layers efficiently capture electromagnetic waves across wide frequency ranges, enabling the creation of sustainable, self-powered devices such as remote sensors and Internet of Things (IoT) systems. In stealth technology, absorbing layers reduce radar visibility, enhancing the performance of aircraft and naval systems. They also play a vital role in communication networks by minimizing stray signals and mitigating electromagnetic interference, making them indispensable in today’s interconnected world.

Fast radio bursts (FRBs) are one of the greater mysteries facing astronomers today, rivaled only by gravitational waves (GWs) and gamma-ray bursts (GRBs). Originally discovered in 2007 by American astronomer Duncan Lorimer (for whom the “Lorimer Burst” is named), these short, intense blasts of radio energy produce more power in a millisecond than the sun generates in a month.

In most cases, FRBs are one-off events that brightly flash and are never heard from again. But in some cases, astronomers have detected FRBs that were repeating in nature, raising more questions about what causes them.

Prior to the discovery of FRBs, the most powerful bursts observed in the Milky Way were produced by , which are visible from up to 100,000 light-years away. However, according to new research led by the Netherlands Institute for Radio Astronomy (ASTRON), a newly detected FRB was a billion times more radiant than anything produced by a neutron star.